Field of the Invention
The invention provides multifunctional polymers comprising a repeat unit having a pseudo-cationic moiety, a repeat unit having a hydrophobic moiety, and a third repeat unit. In one embodiment the polymer has a weight-average molecular weight of less than about 10,000 Da. In another embodiment the polymers exhibit antimicrobial activity. The polymers may be prepared by known polymerization methods, such as radical or condensation polymerization. Depending upon the repeating unit types and ratios, the resulting polymers can have a wide variety of physical and chemical properties. The multifunctional polymers of the invention can be employed in a wide variety of compositions. Also disclosed is a method of providing antimicrobial activity through the use of the multifunctional polymers.
Description of Related Art
Antimicrobial compounds are widely used in many formulations, where they may assist in killing or inhibiting the growth and presence of microbes as bacterium, fungus, or protozoan, or combinations thereof. In the personal care arts antimicrobial compounds may be called “preservatives,” while in non-personal care applications—such as adhesives, coatings, inks, membranes, textiles, and paints—antimicrobial compounds may be called “biocides.” Regardless, regulatory and environmental concerns have put limits on the selection and usage of traditional preservatives. Non-traditional antimicrobial compounds, such as multifunctional polymers, have attracted much attention in the chemical industry. Antimicrobial polymers are nonvolatile, do not penetrate the skin, have better long-term efficiency and possibly higher selectivity compared to traditional preservatives. Antimicrobial polymers also minimize environmental problems by minimizing residual toxicity.
Multifunctional polymers are described in the following disclosures, each of which is incorporated herein by reference. De Grado, et al., in J. Am. Chem. Soc., 2005, 127, 4128, and U.S. Pat. Appl. No. 2006/0024264 disclose the synthesis and uses of amphiphilic polymethacrylate derivatives as antimicrobial agents. Kuroda, et al., in Chem. Eur. J., 2009, 15, 1123, describes the role of hydrophobicity in the antimicrobial and hemolytic activities of polymethacrylate derivatives. Gellman, et al., in Org. Lett., 2004, 4, 557, discloses the biocidal activity of polystyrene derivatives bearing cationic properties through reversible amine protonation. U.S. Pat. No. 6,214,885 describes the use of polymers containing β-hydroxyalkylvinylamine units as biocides. U.S. Pat. No. 5,208,016 discloses antimicrobial resin compositions containing ethylene copolymer from radical polymerization of ethylene and dialkylaminoalkylacrylamide co-repeating units.
Other references related to these polymers include the following patents and patent applications: EP 40,498; GB 686,381; 730,463; 870,398; 922,878; 1,286,966; 1,329,033; JP 53,090,397; 57,161,859; U.S. Pat. Nos. 3,449,250; 3,555,001; 4,048,422; 4,058,491; 4,734,446; 4,767,616; 5,229,458; 5,352,729; 5,408,022; 5,449,775; 5,492,988; 5,756,181; 6,025,501; 6,071,993; 6,075,107; 6,299,866; 6,646,082; 6,682,725; 6,737,049; 6,838,078; 6,951,598; 7,033,607; 7,041,281; 7,323,163; 7,326,262; 7,592,040; 7,955,594; US 2005/0152855; 2006/0024264; 2007/0082196; 2007/0161519; 2007/0238807; 2009/0029129; 2009/0312214; 2010/00029838; 2010/00298504; 2010/0130678; 2010/0137455; 2010/0174040; 2011/0060166, and WO 2010/0014655; 2010/031144 and PCT/US13/030115.
Accordingly, there is a need for multifunctional polymers to alter or improve the physicochemical properties of such polymers.